Speaking as an armchair lawyer you can make your own choices.

Being from the St. Louis area I can say that these guys also liked to collect, buy, sell and trade guns. Still dealing that often without a license caused them a good bit of headache.

http://www.thehighroad.org/showthread.php?t=42686

I guess what I do not understand is why anyone would go to the trouble of getting an FFL if it is perfectly fine to run a gun business without one. Surely almost all dealers love guns and love to buy and sell them. And probably most of them collect them?